How to Change a Crank Seal on a KTM 50
- 1). Disconnect the clutch cable from the fitting on the clutch cover, using a metric wrench.
- 2). Loosen and remove the clutch cover bolts with a metric socket and ratchet. Save the bolts. Tap the outer edges of the cover with a rubber mallet to dislodge the cover from the crankcase. Remove the cover and discard the clutch-cover gasket.
- 3). Remove the bolts from the clutch pressure plate. Save the plate and the bolts. Pull the clutch plates and spacers out of the clutch housing by hand. Remove the bolts at the clutch basket. Pull out the basket by hand to expose the crank seal.
- 4). Attach a seal extractor tool onto the exposed end of the crankshaft and the crank seal. Turn the main bolt at the center of the tool clockwise with a metric wrench to remove the seal.
- 5). Push a new crank seal onto the outer end of the crankshaft by hand, making sure the rubber side of the seal is facing in. Position the open end of a 1.5-inch deep socket on the outer face of the seal as a driver. Hold the socket in place with one hand.
- 6). Tap the outer end of the socket with the rubber mallet to seat the seal fully into the crankcase and against the backing rim.
- 7). Reattach the clutch basket with the saved bolts. Reinstall the clutch plates and spacers into the basket. Reattach the pressure plate and tighten the saved bolts to 27 foot-pounds with a torque wrench.
- 8). Install a new clutch cover gasket on the face of the crankcase. Reattach the clutch cover with the saved bolts; tighten them with the socket and ratchet. Reconnect the clutch cable to the fitting on the cover.
- 1). Loosen and remove the timing cover bolts at the left side of the crankcase. Save the bolts. Pull the cover off by hand and set it aside.
- 2). Disconnect the ignition wires from the stator and timing plate inside the timing housing with a screwdriver. Remove the bolts at the timing plate with a metric socket and ratchet. Pull the stator and timing plate assembly out of the housing by hand.
- 3). Attach a seal extractor tool onto the exposed end of the crankshaft and the crank seal. Turn the main bolt at the center of the tool clockwise with a metric wrench to remove the seal.
- 4). Push a new crank seal onto the outer end of the crankshaft by hand, making sure the rubber side is facing in. Position the open end of a 1.5-inch-deep socket on the face of the seal as a driver. Tap the outer end of the socket with the rubber mallet to seat the seal fully into the crankcase and against the backing rim.
- 5). Reinstall the stator and timing plate assembly with the saved bolts. Reconnect the ignition wires with the screwdriver. Reattach the timing cover, and tighten the saved bolts.
Right Side Seal
Left Side Seal
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